1. Technical Field
The present invention relates generally to voice communications and, more particularly, to Voice over Internet Protocol (VOIP) caller authentication by voice signature continuity.
2. Description of the Related Art
Traditional Public Switched Telephone Network (PSTN) telephone networks provide a method (hereinafter referred to as caller identification or caller ID, in short) that allows a called party to identify a calling party. With the advance of the Voice over Internet Protocol (VoIP) environment, the secure authentication of caller ID has disappeared. A calling party can spoof the caller ID at will. Moreover, even when the caller ID is initially correct, the corresponding voice path of the Session Initiation Protocol (SIP) session can be hijacked such that a called party talks to a different person than that identifier by the caller ID after the SIP signaling path is successfully established.
Although there are some mechanisms in SIP/VoIP to provide authentication and security for VoIP calls, these mechanisms all require a public key infrastructure (PKI) to provide the certificate and encryption key for each phone. A PKI for every phone does not currently exist, and will not be available for the foreseeable future. Moreover, VoIP converted traditional phones (by a VoIP gateway or a VoIP conversation device directly attached to a Plain Old Telephone Service (POTS) phone) and most conventional VoIP phones do not implement the advance authentication and encryption mechanism.